"We encourage people to remain calm and not spread unfounded rumors until more information becomes known," the statement said. "We reiterate the call ... upon parents to supervise the whereabouts of their children at all times in order to ensure their safety. We urge parents to keep their children at school and go about their daily routine."

Al-Wefaq, Bahrain's main Shiite opposition party, said the teen was killed when he was hit by bird pellets shot by Bahraini security forces.

The unrest was spurred by movements in Tunisia and Egypt. But demonstrations in Bahrain failed to gain the traction of other Arab Spring uprisings after a crackdown by authorities in the island state. The crackdown was backed by troops from nearby Saudi Arabia and the United Arab Emirates.

In November of that year, Bahrain's Independent Commission of Inquiry issued a report critical of authorities' reactions to the protests.

The independent commission, set up by the king, concluded that the police had used excessive force and torture in their response to the protests in Sunni-ruled, Shiite-majority country.

Abuse of detainees in the crackdown included beatings with metal pipes and batons, and threats of rape and electrocution, according to Mahmoud Cherif Bassiouni, the commission chairman.

The report recommended reforms to the country's law and better training of its security forces, as well as other measures.